SAG-AFTRA members will rally Wednesday at the La Brea Tar Pits in a show of unity for the union’s four-month-old strikeagainst Bartle Bogle Hegarty. Members will meet at the union’s headquarters in Los Angeles at noon and then march to the nearby Tar Pits to hear speakers denounce the struck ad agency.

The strike is part of the union’s Ads Go Union campaign to organize non-union commercials. SAG-AFTRA also is gearing up for negotiations for a new commercials contract, which generates more than $1 billion in annual wages for its members.

SAG-AFTRA president Gabrielle Carteris, national executive director David White and Los Angeles Local president Jane Austin will lead the rally. Reps from other labor organizations expected to attend include Steve Dayan, secretary-treasurer of Teamsters Local 399; Rusty Hicks, president of the LA County Federation of Labor; John Acosta, president of Musicians Local 47; Tom Davis, second international vp of IATSE, and Kevin James, president of the Board of Public Works and the city’s chief film liaison.

SAG-AFTRA struck BBH on September 20 after the ad agency declared that after 20 years it was no longer a signatory to the union’s commercials contract. Since then, the 160,000-member performers union has tried to force the agency to re-sign its contract through mass rallies, picketing, NLRB complaints, celebrity endorsements and shaming.

The union has instructed its members “not to accept any work for BBH, which is illegally attempting to abandon its union contract with SAG-AFTRA.”